<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>jQuery Example</title>
<script src="https://cdn.staticfile.org/jquery/3.5.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
  $("#changeTextButton").click(function(){
    $("#textContent").text("文本已更改！");
  });
});
</script>
</head>
<body>

<p id="textContent">这是一个段落。</p>
<button id="changeTextButton">更改文本</button>

</body>
</html>
